Machine-gun.



A. M. BROTHERSTON.

MACHINE GUN.

.APFLICATION FILED JAN- 31; l9lfi. v

Patented Feb.' 2 1917 Mwnfor nrrnn sraa ns ainxannnn M. nnorrrnnsron, or Monorron, NEW BRUNSWICK, CANADA, Assrenon or one- A F ro HOLMES A. FRANK,

orMILLAnron, NEW BRUNSWICK, CANADA.

MACHINE-GUN.

' arness.

To all whom it may concern:

Be it known that I, ALEXANDER M. Brown I nRsToN, a citizen of the Dominion of Canada, and resident of the city of Moncton, in the Province of New Brunswick and Dominion of Canada, have invented certain new and useful Improvements in Machine- Guns, of which the following is a full, clear, and exact description.

This invention relates to improvements in machine guns, and the object of the invention is'to provide an electrically operated machine gun so constructed and arranged that the working thereof, beyond aiming, will under ordinary circumstances be entirely automatic. A further object is to provide a machine gun'which may if desired be operated by hand in the usual manner and thrown into 30 or out ,ofautomatic operation vin a moment of time as required. Still another object is to provide an automatic oscillating gun. Various other objects and advantages of 25 the gun will be apparent from thefollow mgdescription.

The gun consists essentially of a barrel breech and a support, to Which are applied an electric motor operated by current de- 50 rived from a storage battery carried on the gun-or from any other source of energy.

The motor is connected to the mechanism of I the gun in such a manner that it will simult'a neously" operate a cartridge conveyer and 35 the breech mechanism, and if desired, an oscillating device, so that the gun will swing steadily back and forth through a given angle, thus maintaining a fan shaped zone of fire. The speed of fire may be regulated to by varying-the speed of the motor. If desired, the motor may be disconnected from 'theoscillating mechanism and from the breech mechanism independently, so that the gun may be operated by hand in the usual 5 manner. When, however, the entire auto;- matic operating mechanism" is in gear, the gun once aimed and started will continue to fire without any attention as long as the supply of cartridges lasts. In the drawings which illustrate the invention:

- Figure 1 is a side elevation partly in section.

Fig.2 is a rear elevation. 1 Fig. 3 is a section on the line 3 3, Fig. 1.

Specification of Letters Patent.

rear end of the breech frame.

the breech b'olt;

Patented Feb. 20, 1917.

Application filed January 31, 1316. Serial No. 75,375.

Fig. 4 is a vertical longitudinal section of the breech mechanism.

Fig. 5 is a plan view of the oscillating mechanism. v

Referring more particularly to the drawings, 11 designates the barrel and 12 the breech frame in which the barrel is secured? A breech bolt 13 is slidably mounted in the breech frame, and is operated by means of toggle .levers 14 and 15 pivotally connected together, the former being also connected with the breech bolt and the latter With the The breech bolt contains a spring operated firing pin 16 having catches 16 and 16", and also carries a spring pressed sear 17 having a rearwardly projecting arm 17. The toggle lever 14 is provided at its point of connection to the bolt with a cam 14L, which engages the firing pin catch 16 and retracts the firing pin during the opening movement of firing pin catch 16*" engages behind the sear 17. On the final closing of the breech when the toggle straightens out, a trigger pin 18 on the lever 14 depresses the sear arm 17 and disengages the sear from the firing pin catch. In this way, the gun is automatically. fired at the moment the breech closes.

' The barrel and breech frame are mounted in a cradle 19, which is supported on trunnions 20 in a suitable yoke 21, so that the barrel may be oscillated in a vertical plane to give the necessary elevation. "The yoke 21 is pivotally mounted on a table 22, so that the gun maybe oscillated in a horizontalplane.

A suitable motor 23 is'mounted on the barrel or cradle, and-takes current from a storage battery 24 or other suitable source of energy through a suitable switch, located by preference in the directing handle 25. The motor drives a gear 26 mounted on the shaft '27. Thisshaft is connected byvmeans of a suitable clutch 28 with a shaft 29 carrying a single toothed gear 30, adapted to mesh with a pinion 31, connected to operate the cartridge belt'feed spool 32 mounted under an opening 33 in the bottom of the breech frame. A bevel pinion 34 ismounted on the .When fully retracted, the

rear end of the-shaft 29 and meshes with a thus be seen that as the crank disks 36m- It will volve, they will produce a reciprocation of the breech bolt. shaft 29, the single tooth of the gear 30 Will engage the pinion 31, and thus turn the cartridge belt feed drum 32 the distance of one cartridge. The positioning of the single tooth of this gear 30 is such that the shift of the cartridge belt will occur immediately the bolt is withdrawn. As the bolt pauses momentarily when its direction of movement is reversed, there will be ample time for the belt to shift and bring a new cartridge into line with the bolt. As the bolt advances, it drives the cartridge ahead of it out of the belt and into the barrel. -lVhen it again retreats, it extracts the empty shell and ejects the same in any suitable manner. If a handle 38 is applied to one of the crank disks, the gun may be operated manually and independent of the motor by releasing the clutch 28.

Any suitable mechanism may be provided for automatically oscillating the gun, such as the internally toothed link 39 pivotally mounted on the table 22, and containing a pinion 4O driven by a pinion 41 from the gear 42, mounted concentrically with the trunnion 20 and driven from the shaft 27. By throwing out the catch 43, which holds the pinion ll up, the pinion will drop out of mesh with the .idler gear 44 and the oscillat 'ing mechanism may be disconnected, so that thegun will remain stationary. The pivotal support of the link 39 is slidable toward and away from the center of lateral oscillation of the gun. The link extends in the same normal direction as the barrel, and as the pinion 4:0 revolves, it travels along one side of the rack and around the end, and then travels back again, being held always in engagement with the rack teeth by the centrallylocated guide. As the pinion can obviously travel only in the path indicated in Fig. 5, it moves the link in and out as it passes over the ends.

In common with all rapidly fired guns, the barrel of this gun requires cooling, and for this purpose, a reservoir 44 for the cooling liquid is provided, which is suitably shaped to have a common lowest point 45 at all elevations within the range of the gun. A liquid circulating device such as a centrifugal pmnp-l( is operatively connected with the motor 23 and draws liquid from the lowest point 4:) of the reservoir through a radiator 47, and discharges it over the entire length of'the barrel by means of a perforated pipe 48 extending longitudinally above the bai t'cl. tinned through or beside the reservoir to operate a fan 49, for the purpose of forcing a strong current of air through the radiator.

The fan and air passages through the radiator are entirely separate from the reservo r, so that in cold weather, no steam,

which On each revolution of the The shaft 27 may be conwould betray the position of the gun or esult in loss of liquid, will be given off.

It is thought that the operation of the g In will be readily understood from the fof'egoing description and therefore only a summary of the capacity is required. The motors required are quite small and light, and consume only a small amount of current, so that a number of guns may be oiperated for many hours by current froml a storage battery light enough to be easily carried by one man. As' these guns are u ually operated only a few minutes at a time, it will be readily understood that this method of operation is reliable. Modern methods of warfare, especially trench warfare, include the use of so much electrical apparatus that current supply other than that from storage batteries is nearly always available. The great advantage of operating a gun by motor is that the gunners entire attention may then be devoted to aiming the gun. Furthermore, the gun may be operated at uniform speed for long periods of time, without any fatigue to the gunner and without causing any inadvertent movements such as sometimes occur with hand operated guns. lVhen desired, the operator, by throwing out the clutch 28, may stop the automatic operation of the gun while leaving the motor running, thus enabling the barrel to be very quickly cooled, and also permitting the gun to be manually fired a few shots at a time. Once the gun has been set in operation, it will continue to fire as long as the supply of cartridges lasts, covering a comparatively wide front. This is obviously a great advantage as the defense will be continued even should the gunner be killed or disabled. A further ad mntage is that the gunner may remain completely sheltered and observe the etl'ect'of fire through a periscope or by other means, exposing only one hand at various times to control the gun.

\Vhile specific forms of firing pin -mechanism, breech bolt operating mechanism, and oscillating mechanism have been shown and described, it must be understood that the invention is not limited to these particular forms, as other more suitable mechanisms may be produced. Any suitable mechanism may be provided toreleasably lock the gun at any angle of elevation or depression, or at any angle to the right or left of the normal direction.

Having thus described my invention, what I claim is- 1. In a gun, a table, a pi-rotally mounted gun support thereon, an internally toothed link connected with said table, a pinion carried by the gun support, and means for operating said pinion to oscillate the gun.

2. In a. gun, a revoluble yoke, a cradle trunnioned in said yoke, means connected with the yoke for oscillating the gun in a predetermined plane, driving mechanism for said oscillating means carried on the cradle, and a gear connecting the driving means and oscillating means concentric with the cradle trunnions.

8. In a gun, a shaft, a crank driven by said shaft at the same speed as itself, a breech block, operative connection between v the breech block and crank, a cartridgefeed drum, a drive gear therefor, a one-toothed gcanmounted on the shaft holding said drum gear against revolution except during open. breech position.

4.. In a gun, a breech mechanism, a cartridge feed mechanism, a common drive shaft for said .mechanisms a mechanical cooling mechanism, a motor direct connected and, feed mechanism drive shaft. 5. In a gun, a motor, a mechanical coolngmechanism direct connected to the motor, breech operating and cartridge feeding mechanisms releasably connected to the motor, and a gun oscillating'inechanism releasably connected to the motor independent of .the breech operating and cartridge feeding mechanisms.

In Witness ivhereof, I have hereunto set my hand, in presence of two witnesses.

i Witnesses r S. L. W. ALLEN, G. M. MORELAND.

ALEXANDER M. BROTHERSTON. v

tosaid cooling mechanism, and a clutch conlnection between the motor and said breech 

